TBD

High Energy Seminar

Wednesday, October 18, 2017 - 12:30pm

Phillips Auditorium

Black Holes: the Nemesis of Galaxy Formation

Speaker:

Richard Bower

Institution:

Durham University

Abstract

Galaxies fall into two clearly distinct types: `blue-sequence' galaxies that are rapidly forming young stars, and `red-sequence' galaxies in which star formation has almost completely ceased. Most galaxies more massive than 3 x10^10 Mo follow the red-sequence while less massive central galaxies lie on the blue sequence. In my talk, I'll argue that these sequences are created by a competition between star formation-driven outflows and gas accretion on to the supermassive black hole at the galaxy's centre. The rapid transition between galaxy types occurs as the hot gas corona become hot enough to trap star formation driven outflows, resulting in a rapid phase of black hole growth. This picture explains a remarkable range of the observed properties of the Universe, from the host halo masses of luminous quasars to the transformation of galaxy morphologies.